TechCrunch's Michael Arrington has a solid analysis of Facebook's current financial system, and his outlook isn't good. To boot, he says, Facebook Chief Financial Officer Gideon Yu has been spotted in Dubai, possibly meeting with investors to raise more cash for the company.

Here are Facebook's current problems, per Arrington: Three-quarters of its users are now outside the U.S., many in countries where bandwidth and server costs are more expensive and advertising dollars are less reliable. Hardware costs, while they're lower than they were in the original dot-com era, are still expensive. He's right on pretty much all counts.

The ironic thing is that everything we've heard points to CEO Mark Zuckerberg running a tight ship at Facebook. It's no Southwest Airlines, but for Silicon Valley, Facebook's cheap. Zuckerberg's hardly the picture of Valley excess, with frequent anecdotes describing his fleece-and-sandals dress code, fast-food diet, and spartan living accommodations. Facebook's employees' salaries aren't high by Valley standards--the company attracted talent in part based on the opportunity to work for a buzzworthy company with a potentially huge cash-out down the road. We've also heard that Facebook's goal of hitting 1,000 employees by the end of 2008 has been scrapped, and that for the near future it'll stay where it is now (between 750 and 800). The company admirably steered clear of goofy Google-like perks (like the whole "free food" thing) even when it was at the top of the Valley pecking order with no recession in sight.

But the site is growing so fast and getting so big that it's going to be expensive no matter how many company parties are catered by pizzerias instead of sushi bars, and the albatross around Facebook's metaphorical neck is its advertising-dependent business model. As Arrington wrote, Facebook may not be currently in a position where it can keep its bank accounts up to speed with its growth. Everyone's predicting that ad spending is going to take a nosedive in 2009, and social networks are a fresh enough destination in the ad industry so that advertiser confidence in them just isn't up to speed yet. In other words, Facebook's revenue already isn't good, and Zuckerberg recently said he hoped the company would be profitable in three years. At this rate, the company might not have three years.

Facebook responded to the jittery press on Friday afternoon: "As a matter of policy, we don't comment on market speculation or rumor about our finances," a company statement read. "Facebook is well positioned both financially and within the market and any thoughtful attempt to model our business should reflect that. Our advertising business has great depth and breadth. While no ad business can ever be 100 percent recession proof, the breadth of our advertiser base and the innovative products we offer bolster our position in the current cycle. We've also been closely managing the business so we can continue to hire great people and scale. While we've achieved certain milestones, we are deeply committed to even greater business success in the future."

For the past year, there has been some moderate buzz about "Facebook Wallet," a PayPal-like transaction system that could give the social network an alternate revenue source. But the last we heard, a source in the app development space said that when Google Checkout veteran Ben Ling left his short stint at Facebook, it was still nowhere near completion.

Update: "Facebook is not currently in a position where it can keep its bank accounts up to speed with its growth" was changed to "Facebook may not be currently in a position where it can keep its bank accounts up to speed with its growth." Since Facebook is a privately-held company and does not disclose much of its financial data, it's more accurate to not be quite so definitive.